1. Field of the Invention
This invention relates to a means for fabricating a bead assembly utilized in the construction of a tire. Specifically, the instant invention relates to a means and method for applying a filler to a bead whereby the filler is wrapped about the outer circumference of the bead and the ends of the filler are joined to completely encompass the bead. The instant invention employs an angled orientation of the end of the filler with respect to the radius of the bead in combination with offset application of the leading and trailing ends of the filler in order to facilitate the joining of the leading and trailing ends of the filler.
2. Description of the Prior Art
Apparatus for applying a filler to a bead is well known in the art as disclosed by U.S. Pat. No. 3,909,338 to Leblond et al. which discloses an apparatus and method for applying an elastomeric bead filler to a bead ring. The apparatus of Leblond has a pully for supporting a bead ring and a unit for advancing the filler strip to the outer periphery of the bead ring. Other units are provided for cutting the strip to a length corresponding to the circumference of the periphery of the bead ring, and for applying the strip to the periphery of the bead ring. U.S. Pat. Nos. 4,226,663 and 4,298,421 to Pirovano et al. discloses a device for automatically loading a bead core to an apparatus which associates an elastomeric filler with the bead core and for unloading the bead core with the filler. The device employs two jaws for loading the bead core and means for controlling the opening of the jaws. A mechanism is employed for grasping each end of the filler in order to butt splice the ends of the filler about the bead.
U.S. Pat. No. 3,787,263 to Yonekawa et al. relates to a method and apparatus for automatically sticking an apex rubber strip on bead rings for use in pneumatic tires whereby a number of bead rings may be fed to and disposed on a pair of driving rollers, one by one, and a continuous apex rubber strip may be fed to the outer periphery of each ring. Successive steps of sticking the forward end of the apex rubber strip on the outer periphery of each bead ring, rotating the driving rollers, detecting the arrival of the forward end of the apex strip stuck on the outer periphery of each bead ring at its final position around the bead ring, obliquely cutting the rear end of one turn of the apex rubber strip, restarting the rotation of the driving rollers and sticking the rear end of the apex rubber strip thus cut on the bead ring, and replacing the bead ring with a new bead ring, are performed automatically.
The prior art also includes U.S. Patent No. 4,354,892 to Tarantola et al. which discloses an apparatus provided with means suitable for stretching a filler when it is pulled into rotation with a bead core on the drum to stiffen the filler and resist bending, and therefore maintain the filler substantially in the drum midline. The apparatus of Tarantola et al. is further provided with means for discharging the bead core/filler assembly in a plane unchanged with respect to that determined by the stretching needs in order to permit the collection of various filler bead core assemblies one after another. A pair of fingers are utilized to splice the ends of the filler.
U S. Pat. No. 4,410,389 in the name of Cole et al. discloses a continuously operating machine for forming filler bead core assemblies comprising a filler applicator where the bead core and an endless length of filler material in cylindrical form are disposed adjacent to one another, the filler material subsequently being rotated outwardly to lie on the outside of the bead core.
The prior art devices are generally not adapted for the application of wide filler members to a bead without employing relatively complex application mechanism, especially for joining the ends of the bead filler. The instant invention solves this problem by providing a relatively simple mechanism which is capable of applying wide bead filler members to a bead wherein a tension gradiant is employed during the application of the filler member in combination with an offset application of the leading and trailing ends of the filler in order to provide application of the relatively wide filler to the bead wherein the application process is automatically performed by the relatively simple applicator mechanism.